Experimental Investigation on Mechanical and Durability Properties of Concrete with Partial Replacement of Cement by Silica Fume

Abstract Durability of concrete structures exposed to aggressive environments is a major concern in modern construction practice. Acid attack significantly deteriorates concrete by dissolving cement hydration products, leading to strength loss and reduced service life. In this study, an experimental investigation was carried out to evaluate the mechanical and durability performance of concrete with partial replacement of cement by silica fume. M30 grade concrete was designed as per IS 10262:2019, and cement was replaced with silica fume at 0%, 5%, 10%, and 15% by weight. Mechanical properties were assessed through compressive strength and split tensile strength tests, while durability was evaluated using water absorption and acid resistance tests. The results indicated that silica fume significantly improves strength, reduces permeability, and enhances resistance to acid attack. Among the mixes studied, 10% silica fume replacement exhibited optimum performance in terms of both mechanical and durability properties. The study confirms that silica fume concrete is suitable for structures exposed to aggressive acidic environments. Keywords: Silica fume, Acid resistance, Durability, Compressive strength, Water absorption, M30 concrete.